1. Field of the Invention
The invention relates to a device for transmitting electrical signals by means of sliding contacts between parts that are movable relative to each other. Transmission systems of this kind are used preferably in linear embodiments, or in cylindrical or plate-shaped embodiments for rotating systems, also called slip rings or rotary joints. A sliding contact, often referred to as brush, or a plurality of sliding contacts is disposed to slide on a slide-track of electrically conducting material, the sliding contacts also being of an electrically conducting material. An electric current can be transmitted by electrical contact between the slide-tracks and a contact.
2. Description of Relevant Art
Sliding contact arrangements are used for example in a linear embodiment in crane installations or other conveyor systems for effecting transmission between a movable crane and a stationary control unit. Another field of use of sliding contacts of circular design, also known as slip rings or rotary joints, is that of transmission between parts that are rotatable relative to each other. A typical field of application, for example, is in computer tomographs between a rotor which carries an X-ray tube and a detector, and a stationary evaluation unit which processes and displays image data. Often, particularly those rotary joints of small constructional sizes, are sliding contacts on a metallic basis, for example in the form of a wire or a thin sheet.
A sliding-contact brush having a plurality of single wires is disclosed in U.S. Pat. No. 2,269,614. With this, it is assumed that at any one instant of time at least one wire will be in engagement with a slide-track.
U.S. Pat. No. 4,483,574 discloses a sliding-contact brush having a multiplicity of slide-wires, which is particularly suitable for application in collectors. Here the wires are of relatively short length, so that they will rest preferably vertically on top of the surface of a collector.
In EP 0 662 736 A1 a multiple-wire brush having two to five wires is disclosed, these lying adjacently in the groove of a slide-track with the wires simultaneously contacting the groove of the slide-track.